Acute mortality E-R functions carry no information on YOLL, but we try to estimate a typical value based on plausible upper and lower bounds.

Chronic mortality E-R functions, by contrast, allow a determination of YOLL at least in principle, although in practice there are large uncertainties in the extrapolation from the study population to the general population.

We apply our YOLL estimates to a comparison of mortality costs with morbidity costs, for particles and for ozone.

The costs of acute mortality turn out to be small compared to morbidity.